DETAILED DESCRIPTION OF EMBODIMENTS

[0019] The present invention as applied to a foldable portable telephone will be described below with reference to the drawings. The foldable portable telephone of the invention includes a flat main body case 1 and a lid case 2 , as shown in FIG. 1 , FIG. 2 ( a ), and FIG. 2 ( b ). An upper end of the main body case 1 and a lower end of the lid case 2 are connected to each other by a hinge mechanism 6 . Open-close manipulation can be performed from an opened state of the lid case 2 as shown in FIG. 1 to a closed state of the lid case 2 as shown in FIGS. 2 ( a ) and 2 ( b ). A foldable casing is thus constructed.

[0020] The main body case 1 has a rear portion provided with an extensible antenna 3 . The main body case 1 has an inner surface provided with a group of inner surface manipulating keys 11 including an offhook key 11 a, an onhook key 11 b, and numerical keys 11 c, etc. The inner surface has a lower end portion provided with a speech delivery portion 4 incorporating a microphone. Arranged on the inner surface of the main body case 1 is an open-close detection switch 17 for detecting open-close state of the lid case 2 . The open-close detection switch 17 is turned on by closing the lid case 2 , and is turned off by opening the lid case 2 .

[0021] The portable telephone described comprises a message key 12 , an up key 13 , and a down key 14 . These keys 12 , 13 , 14 are so arranged on a side portion of the main body case 1 as to be exposed to the outside even when the lid case 2 is in its closed state. Accordingly, the keys can be depressed not only when the lid case 2 is in its open state, as shown in FIG. 1 , but also when the lid case 2 is in its closed state, as shown in FIGS. 2 ( a ) and 2 ( b ). The message key 12 , the up key 13 , and the down key 14 each perform different functions depending on whether the lid case 2 is opened or closed, as will be discussed below.

[0022] On the other hand, the lid case 2 has an inner surface provided with a main display 21 . The inner surface has an upper end portion provided with a speech receiving portion 5 incorporating a speaker. The main display 21 shows date and time, various menus, content of a received message, a telephone number and name of the caller when an incoming call is received, or a telephone number of a calling party when the user makes a call and the like in the same manner as in the prior art.

[0023] The lid case 2 has a rear portion provided with an auxiliary display 22 as shown in FIG. 2 ( b ). The auxiliary display 22 shows the number of incoming calls and received messages, a telephone number of the caller when a call is received, name of a received message sender, and content of a received message, etc.

[0024] FIG. 3 shows the electrical construction of the foldable portable telephone described above. With the foldable portable telephone, a telephone circuit 15 is connected to the extensible antenna 3 as illustrated, and processes the signal for a call and data communication with other portable telephone or with an ordinary telephone connected to the subscriber's telephone line.

[0025] The operation of the telephone circuit 15 is controlled by a control circuit 16 having a microcomputer. A microphone 41 and a speaker 51 are connected to the control circuit 16 , respectively, so that the voice of outgoing speech can be inputted, and the voice of incoming speech can be outputted.

[0026] Connected to the circuit 16 are the main display 21 , the auxiliary display 22 , the group of inner surface manipulating keys 11 , the message key 12 , the up key 13 , and the down key 14 , respectively. A backlight 18 is also connected to the circuit 16 for illuminating a display surface of the main display 21 and the auxiliary display 22 . The open-close detection switch 17 is connected to the circuit 16 .

[0027] Further, the foldable portable telephone incorporates a secondary battery (not shown) serving as a power source. Connected to the control circuit 16 is a power supply switch 19 for turning on/off the supply of power from the secondary battery to the telephone circuit 15 , the microphone 41 , the speaker 51 , the main display 21 , the auxiliary display 22 , and the backlight 18 , respecitvely. The switch 19 is on/off-controlled by the control circuit 16 . When the switch 19 is turned on, the supply of the power from the secondary battery to the telephone circuit 15 , the microphone 41 , the speaker 51 , the main display 21 , the auxiliary display 22 , and the backlight 18 is started. On the other hand, when the switch 19 is turned off, the supply of the power from the secondary battery to the telephone circuit 15 , the microphone 41 , the speaker 51 , the main display 21 , the auxiliary display 22 , and the backlight 18 is stopped. The power source of the device body is thus set to an on/off state.

[0028] With the foldable portable telephone, when the power source of the device body is off, the up key 13 and the down key 14 are held depressed at the same time for at least the predetermined period of time with the lid case 2 closed to cause the power source to be turned on. Further, in the same manner as in the prior art, the onhook key 11 b is held depressed for at least the predetermined period of time with the lid case 2 opened to cause the power source to be turned on.

[0029] The onhook key 11 a and the numerical keys 11 c are thereafter manipulated with the lid case 2 opened, so that the user can speak with a calling party using the speech delivery portion 4 and the speech receiving portion 5 .

[0030] With the lid case 2 opened, the message key 12 described performs a function stated below. The message key 12 is held depressed for at least the predetermined period of time during incoming call waiting state to set or cancel a message mode for answering with a message, for example, saying “I am not available to speak on the phone now” when there is an incoming call. The message key 12 is held depressed for at least the predetermined period of time while the user speaks with a calling party to start recording content of talking on the phone, and is thereafter held depressed again for at least the predetermined period of time to stop recording. The message key 12 is held depressed for at least the predetermined period of time upon receiving an incoming call, immediately executing answering operation of reproducing the message, for example, “I am not available to speak on the phone now.” Further, the message key 12 is depressed for shorter than the predetermined period of time to have information on the message mode including the content of the message stated above, etc. shown on the main display 21 .

[0031] On the other hand, when the lid case 2 is in its closed state, the message key 12 performs the function stated below. In the case where the message key 12 is held depressed for at least the predetermined period of time during incoming call waiting state, or in the case where the key 12 is held depressed for at least the predetermined period of time while the user speaks with a calling party, or in the case where the key 12 is held depressed for at least the predetermined period of time when an incoming call is received, the message key 12 performs the same function as when the lid case 2 is in its open state. In other words, the message key 12 is held depressed for at least the predetermined period of time during incoming call waiting state to set/cancel the message mode. The key 12 is held depressed for at least the predetermined period of time while the user speaks with a calling party to start/stop recording content of talking on the phone. Immediately when the key 12 is held depressed for at least the predetermined period of time upon receiving an incoming call, the answering operation of the message reproducing is executed. Further, the message key 12 is depressed for shorter than the predetermined period of time to turn on the backlight 18 and illuminate the auxiliary display 22 .

[0032] When the lid case 2 is in its open state, the up key 13 and the down key 14 perform functions stated below. The up key 13 or the down key 14 is depressed during incoming call waiting state or while the user speaks with a calling party, increasing or decreasing volume of received speech. When various menus or content of the received message are shown on the main display 21 , the up key 13 or the down key 14 is depressed, scrolling up or down those shown on the display. When there is an incoming call, the up key 13 or the down key 14 is depressed, increasing or decreasing the volume of ring tone.

[0033] On the other hand, when the lid case 2 is in its closed state, the up key 13 and the down key 14 perform functions stated below. The up key 13 or the down key 14 is depressed during incoming call waiting state, successively having various information including the number of incoming calls and the number of received messages, etc. shown on the auxiliary display 22 . The up key 13 or the down key 14 is depressed with the content of the message shown on the auxiliary display 22 , scrolling up or down those shown on the display 22 . When there is an incoming call, the up key 13 or the down key 14 is depressed, increasing or decreasing the volume of ring tone in the same manner as in the lid case 2 open state. When the lid case 2 is in its closed state with the power source of the device body set to on, as described above, the up key 13 and the down key 14 are held depressed at the same time for at least the predetermined period of time, turning off the power source. In the same manner as in the prior art, when the lid case 2 is in its open state, the onhook key 11 b is held depressed for at least the predetermined period of time, turning off the power source.

[0034] FIG. 4 shows the procedure of switching on/off the power source of the device body executed by the control circuit 16 described. When the user turns on the power source of the foldable portable telephone described for the first time, required initial setting like setting ports is performed.

[0035] As illustrated, step S 1 inquires as to whether the open-close detection switch 17 is turned on. When the lid case 2 is in its closed state, the answer for the step S 1 is affirmative, followed by step S 2 to inquire as to whether the power source is turned on. If the inquiry is answered in the affirmative, step S 3 follows to inquire as to whether the up key 13 and the down key 14 are held depressed at the same time for at least the predetermined period of time. If the inquiry is answered in the affirmative, the sequence proceeds to step S 4 to turn off the power source, and thereafter returns to step S 1 , while if the inquiry is answered in the negative, step S 4 is skipped, and the sequence returns to step S 1 .

[0036] If the answer for step S 2 is negative, step S 5 follows to inquire as to whether the up key 13 and the down key 14 are depressed at the same time for at least the predetermined period of time. If the inquiry is answered in the affirmative, the sequence proceeds to step S 6 to turn on the power source, and thereafter returns to step S 1 , whereas if the inquiry is answered in the negative, step S 6 is skipped and the sequence returns to step S 1 .

[0037] When the lid case 2 is in its open state, the answer for step S 1 is negative, followed by step S 7 to inquire as to whether the power source is turned off. If the inquiry is answered in the negative, step S 8 follows to inquire as to whether the onhook key 11 b is held depressed for at least the predetermined period of time. If the answer is negative, the sequence returns to step S 1 , while if the answer is affirmative, the sequence proceeds to step S 4 to turn off the power source, and thereafter returns to step S 1 .

[0038] If the answer is affirmative in step S 7 , step S 9 follows to inquire as to whether the onhook key 11 b is held depressed for at least the predetermined period of time. When the inquiry is answered in the negative, the sequence returns to step S 1 . When the inquiry is, on the other hand, answered in the affirmative, step S 6 follows to turn on the power source, and the sequence returns to step S 1 .

[0039] With the foldable portable telephone of the invention, the up key 13 and the down key 14 provided on a side portion of the main body case 1 are held depressed at the same time for at least the predetermined period of time with the main body case 1 and the lid case 2 folded together, which can switch on/off the power source of the device body, as described above. Accordingly, when the power source of the device body is switched on/off, the user needs not to open or close the lid case 2 , hence a simple procedure in switching on/off.

[0040] With the foldable portable telephone described, when the up key 13 and the down key 14 are held depressed at the same time for at least the predetermined period of time, the power source is switched on/off. In the case where the telephone is carried as placed in a bag, for example, there is extremely low possibility that the up key 13 and the down key 14 are touched and depressed by an article in the bag at the same time, and the keys 13 , 14 are held depressed for at least the predetermined period of time. Therefore, it is unlikely that the power source is switched on/off inadvertently.

[0041] Furthermore, the message key 12 , the up key 13 , and the down key 14 each perform different functions depending on whether the lid case 2 is opened or closed. Consequently, the number of the manual keys is smaller than the case wherein one manual key is formed for one function, whereby the device body is made compact.

[0042] The embodiment described above is intended to illustrate the present invention and should not be construed as limiting the invention set forth in the appended claims or reducing the scope thereof. Furthermore, the device of the invention is not limited to the embodiment in construction but can of course be modified variously without departing from the scope of the invention as set forth in the claims.

[0043] For example, according to the embodiment described, when the up key 13 and the down key 14 are held depressed at the same time for at least the predetermined period of time, the power source is switched on/off. The invention is, however, not limited to the above, and it is possible to use the construction wherein the power source is switched on/off when one of the message key 12 , the up key 13 , and the down key 14 is held depressed for at least the predetermined period of time, or when all the keys 12 , 13 , 14 are held depressed at the same time for at least the predetermined period of time.